Prediabetes: What an A1c of 5.7–6.4 Really Means

“Your A1c is 6.1. You have prediabetes. Watch your diet, and we’ll recheck next year.”

If you’ve heard something like that, you may have walked away unsure whether to worry. After all, it’s only pre-diabetes. Right?

Here’s my view, and it’s a little different from how prediabetes is often described: prediabetes and type 2 diabetes aren’t two different conditions. They’re different stages of the same disease. A diagnosis of prediabetes is a call to action, not a reason to wait and see.

What the numbers mean

The hemoglobin A1c test reflects your average blood sugar over the past two to three months.

	A1c	Fasting glucose
Normal	Below 5.7%	Below 100 mg/dL
Prediabetes	5.7% to 6.4%	100 to 125 mg/dL
Type 2 diabetes	6.5% or higher	126 mg/dL or higher

About one in three American adults has prediabetes, and more than 80% of them don’t know it.

A distinction without much of a difference

The cutoffs above are useful for research, billing, and treatment guidelines. But your body doesn’t flip a switch at 6.5%.

Type 2 diabetes develops over years. It usually begins with insulin resistance, where the body needs more and more insulin to keep blood sugar normal, often driven by excess weight, especially visceral fat around the organs. Eventually, the insulin-producing cells can’t keep up, and blood sugar starts to rise: first into the prediabetes range, then into the diabetes range.

By the time your A1c reaches 5.7%, the disease process is already well underway. And the damage isn’t limited to blood sugar. People with prediabetes already have a higher risk of:

• Heart disease and stroke
• Fatty liver disease
• Kidney disease
• Early nerve and blood vessel changes

An A1c of 6.3% and one of 6.6% represent nearly the same underlying biology. One gets called “pre” and the other gets called “diabetes,” and that label often determines what treatment your insurance will cover.

How insurance uses the label

Many commercial insurance plans cover GLP-1 medications for type 2 diabetes but deny them for prediabetes, even when the patient has significant obesity and a clearly rising blood sugar. In effect, patients are told to wait until the disease gets worse before they can get the treatment that could have stopped it.

I think that’s backward medicine.

Fortunately, there’s been an important shift for Medicare beneficiaries: under the Medicare GLP-1 Bridge, prediabetes with a BMI of 27 or higher qualifies for coverage of Zepbound, Wegovy, or Foundayo at a $50 monthly copay. That’s a real recognition that prediabetes deserves treatment.

Prediabetes is reversible, and diabetes is preventable

This is the encouraging part. Treating prediabetes works.

• Lifestyle change: In the landmark Diabetes Prevention Program, modest weight loss (about 7% of body weight) plus 150 minutes a week of activity reduced progression to diabetes by 58%, and by 71% in adults over 60.
• Metformin reduced progression by about 31% in the same study.
• GLP-1 medications: In a three-year study of tirzepatide (Zepbound) in people with obesity and prediabetes, only about 1% of those on the medication developed type 2 diabetes, compared with about 13% on placebo. That’s a reduction of more than 90%.

What I do when I diagnose prediabetes

When I see an A1c in the prediabetes range, we act:

1. Look at the whole metabolic picture: weight, blood pressure, cholesterol, liver health, sleep, and family history.
2. Set specific, realistic lifestyle goals around nutrition, physical activity, and sleep, rather than a vague “eat better.”
3. Treat excess weight directly when present, including with anti-obesity medications when appropriate and accessible.
4. Consider metformin for some patients, particularly younger people or those with a history of gestational diabetes.
5. Recheck regularly, typically every 3 to 12 months depending on the situation, rather than waiting a year to see what happened. For some patients, home glucose monitoring helps. Read more about our remote patient monitoring.

The goal isn’t just to keep you under 6.5%. It’s to move you back toward normal and lower your long-term risk of heart attack, stroke, kidney disease, and liver disease.

Should you be tested?

The U.S. Preventive Services Task Force recommends screening adults 35 to 70 who have overweight or obesity. Many doctors, including me, also test people with other risk factors, such as a family history of diabetes, a history of gestational diabetes, PCOS, high blood pressure, or fatty liver, at any adult age.

Take action now

If you’ve been told you have prediabetes, or you have risk factors and haven’t been tested, don’t wait for next year. At Aristos Internal Medicine in Spokane, I’m board certified in both Internal Medicine and Obesity Medicine, and treating prediabetes before it becomes diabetes is one of the most rewarding parts of my work.

Schedule an appointment online or call (509) 426-5425. Follow-up visits are available by video throughout Washington. Learn more about our diabetes care and obesity and metabolic health services.